Fix completed runs not appearing in list + add purge-failed endpoint

- Update save_run_cache to also update actor_id, recipe, inputs on conflict
- Add logging for actor_id when saving runs to run_cache
- Add admin endpoint DELETE /runs/admin/purge-failed to delete all failed runs

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

celery_app.py

@@ -14,7 +14,7 @@ app = Celery(
     'art_celery',
     broker=REDIS_URL,
     backend=REDIS_URL,
-    include=['tasks', 'tasks.streaming']
+    include=['tasks', 'tasks.streaming', 'tasks.ipfs_upload']
 )
 
 app.conf.update(